[unreadable] The goal of this proposal is to make a state-of-the-art ultrasound imaging system available for NIH-funded researchers at the University of Wisconsin (UW) Medical School. The Section of Cardiovascular Medicine and the UW Department of Population Health Sciences have a strong history of successful and productive collaborations that have resulted in high-quality research in cardiology and the epidemiology of cardiovascular disease. Acquisition of an ultrasound imaging system will facilitate and significantly enhance the scientific quality of several ongoing NIH-supported research projects described in this grant application. The Siemens Acuson Sequoia C512 is a state-of-the-art, multipurpose instrument for cardiac and vascular ultrasound imaging. All of the funded research studies for which we are seeking a shared ultrasound system will use it as a tool to better understand the physiological consequences of sleep-disordered breathing, hypertension, diabetes mellitus, congestive heart failure, and myocardial infarction. The three "major" users are an ideal group to share instrumentation given their common research interests in sleep-disordered breathing and cardiovascular disease, their need for high-quality ultrasound to assess cardiovascular structure and function, their strong collaborative relationships with the Principal Investigator, and their status as active, R01-funded investigators. All six investigators use several ultrasound-based research techniques including the evaluation of carotid intima-media thickness, brachial artery reactivity, cerebral blood flow, coronary blood flow, and left ventricular systolic and diastolic function. Because diagnostic ultrasound has no known biological effects, serial studies can be performed longitudinally to evaluate various stages of disease processes and their responses to interventions. Since the research equipment needed to perform these studies currently does not exist in the UW Medical School, it must be borrowed or time purchased from an already oversubscribed clinical laboratory, an expensive and inconvenient arrangement. The necessary space, administrative support, supervision, and technical expertise already are in place to assure that the requested equipment will be operable immediately and highly productive at UW. There is significant opportunity for greater collaboration, research productivity, and cost savings if an ultrasound system is made available at the UW Medical School as a shared resource. [unreadable] [unreadable]